Cheng Li is a Professor at Department of Astronomy of Tsinghua University in Beijing. Before he joined Tsinghua in September 2015, he worked at Shanghai Astronomical Observatory (SHAO) as a group leader (2010-2015), and at Max-Planck Institute for Astrophysics (2007-2010) and SHAO (2006-2007) as postdoc. He obtained his PhD from USTC in 2006. His research has been focused on the structure, formation and evolution of galaxies, as well as the large-scale structure of the Universe. He is a member of the SDSS-IV and Subaru/PFS projects. More details can be found on the web for both Cheng Li himself  (http://astro.tsinghua.edu.cn/~cli/) and his group at Tsinghua (https://lig.astro.tsinghua.edu.cn/).Galaxies are evolving ecosystems of multiple components which interplay with each other and are distributed over a wide range of spatial scale, from sub-galactic scales up to scales of dark matter halos. Therefore, in order to have a complete picture of galaxy formation and evolution, one has to obtain observational data with multiple wavebands and different spatial resolutions to probe physical processes both internal and external to galaxies. Current integral field unit (IFU) surveys such as MaNGA are providing resolved spectroscopy for large samples of galaxies in the local Universe, allowing the stellar populations, dust attenuation and gas ionization, as well as star formation histories across the whole galaxy area to be  studied with high accuracy. I will present our recent studies of the MaNGA galaxies. If time allows, I'll extend to larger scales and briefly talk about the content of atomic gas and warm gas in/around low-z galaxies out to scales of dark matter halos.